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    w= 2-2*3^1/2 + 2+2*3^1/2

    what's the argument?

    i keep getting -5/12 pi but the answer says 7/12 pi

    i know that they are the same thing but would i be downmarked for putting the former?
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    (Original post by TPJY)
    w= 2-2*3^1/2 + 2+2*3^1/2

    what's the argument?

    i keep getting -5/12 pi but the answer says 7/12 pi

    i know that they are the same thing but would i be downmarked for putting the former?
    Argument is 0. I presume you've mistyped, as that's entirely real.

    PS: -5/12 pi and 7/12 are not the same

    Edit: It would be marked down.
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    the answer to what you`ve typed is just...4

    could you type the expression on the rhs with brackets? is it a rational term?
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    (Original post by TPJY)
    w= 2-2*3^1/2 + (2+2*3^1/2)i

    what's the argument?

    i keep getting -5/12 pi but the answer says 7/12 pi

    i know that they are the same thing but would i be downmarked for putting the former?

    (Original post by ghostwalker)
    Argument is 0. I presume you've mistyped, as that's entirely real.

    PS: -5/12 pi and 7/12 are not the same

    Edit: It would be marked down.

    (Original post by Hasufel)
    the answer to what you`ve typed is just...4

    could you type the expression on the rhs with brackets? is it a rational term?
    sorry! i forgot to type the 'i'

    but tan(-5pi/12)=-2-root3=tan(7pi/12)
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    (Original post by TPJY)
    sorry! i forgot to type the 'i'

    but tan(-5pi/12)=-2-root3=tan(7pi/12)
    Well the imaginary part is positive, so we're in quadrants 1 or 2.

    And the real part is negative, so it's quadrant 2.

    Hence 7pi/12.

    The fact that tan(7pi/12)=tan(-5pi/12) is irrelevant. The angles are 180 degrees apart.
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    (Original post by ghostwalker)
    Well the imaginary part is positive, so we're in quadrants 1 or 2.

    And the real part is negative, so it's quadrant 2.

    Hence 7pi/12.

    The fact that tan(7pi/12)=tan(-5pi/12) is irrelevant. The angles are 180 degrees apart.
    OHWAITYESISEE

    because arguments are always measured positively from the positive Real axis right? so you measure the obtuse angle? if that's right then i've got it, thanks a lot!
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    (Original post by TPJY)
    OHWAITYESISEE

    because arguments are always measured positively from the positive Real axis right? so you measure the obtuse angle? if that's right then i've got it, thanks a lot!
    You measure from the +ve real axis; Either going anticlockwise up to 180 degrees inclusive of the 180 (a positive angle), or clockwise up to 180 degrees, excluding the 180, (a negative angle)
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    (Original post by ghostwalker)
    You measure from the +ve real axis; Either going anticlockwise up to 180 degrees inclusive of the 180 (a positive angle), or clockwise up to 180 degrees, excluding the 180, (a negative angle)

    hmm, so if it is in the 3rd or fourth quadrant e.g. z=1-root3i
    then you have to say that arg(z) is -pi/3

    you're not allowed to say it's 5pi/3?
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    (Original post by TPJY)
    hmm, so if it is in the 3rd or fourth quadrant e.g. z=1-root3i
    then you have to say that arg(z) is -pi/3

    you're not allowed to say it's 5pi/3?

    That's correct. 5pi/3 is wrong.

    See attached. Slight typo on the bottom one - should be "-pi/2"
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    (Original post by TPJY)
    w= 2-2*3^1/2 + 2+2*3^1/2

    what's the argument?

    i keep getting -5/12 pi but the answer says 7/12 pi

    i know that they are the same thing but would i be downmarked for putting the former?
    I actually came here to argue with you -_-
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    (Original post by nemogirl)
    I actually came here to argue with you -_-
    as did I :sad:
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    (Original post by nemogirl)
    I actually came here to argue with you -_-



    (Original post by ghostwalker)
    That's correct. 5pi/3 is wrong.
    is that just due to convention?

    (Original post by RainbowWithAnI)
    as did I :sad:
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    (Original post by TPJY)
    is that just due to convention?
    No. 5pi/3 and -pi/3 point in different directions. Similar to North and South.

    I've added a diagram to my previous post; there's a typo at the bottom of it.
 
 
 
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